COLUMN: The power of ponds, and how to build one!

If you build it, they will come, says Montgomeryshire Wildlife Trust’s Climate Solution Officer Dan Hodgkiss, who explains there are few better things you can do for wildlife in your garden

“The wind is howling, the rain is filling up the gutters, the sky can’t be seen for clouds.

The weather might be grotty – but this time of year is actually perfect for making a pond. Get it created and filled now and you’ll be just in time for before newts and other amphibians get into full swing with their spawning (though sightings as early as December are increasingly common due to our warming climate).

To get started, you’ll first need to consider where to position your pond. Ponds need light, so it’s no good siting it under a tree or in a dark corner of a garden. If that sunny site is also damp, all the better.

Next, you’ll need to think about what kind of liner you’d like to use. You can get pre-moulded liners, which simply go straight into the ground, or create a pond yourself by digging a hole and lining it.

Where wildlife is concerned, the key thing to bear in mind is pond gradient. The Victorians were very fond of their steep sides, and their rectangular cubes still drown hapless rodents to this day.

Shallow sides with a graded incline will allow an easy way out for any non-pond-life that needs to escape onto dry land, such as hedgehogs, as well as giving easy access in and out for amphibians. If in any doubt, adding a ramp will do the job nicely too.

Your pond should be about 75cm at its deepest, with a shallow shelf of around 30 cm depth. These shallow areas are great for tadpoles and other wildlife, offering warm grazing areas for algae.

If using a flexible plastic liner, you’ll first need to prepare the ground by providing a smooth surface free of jagged edges (particularly glass, stones, nails or screws) which might otherwise puncture the liner. You can do this by covering the surface with fine sand or old strips of carpet.

Once you’re happy that the liner is sitting pretty and free of bubbles, you can fill your pond. The weight of the water will further help form its shape.

Most pond-liners degrade if exposed directly to sunlight, so be sure to weigh down the edges with stones and plants, which will also keep the liner from slipping. If planting up a pond from scratch, there are a range of native plants which support wildlife and look fantastic doing it!

Yellow Flag Iris, White Water Lily and Yellow Water Lily are beautiful, pollinator-friendly species that prefer deeper water for their roots. Whichever you choose, try to source plants carefully as there’s a danger of introducing non-native invasive species.

Floating species such as Frogbit and various pondweeds can also help fill those spaces, remembering the golden ratio for encouraging wildlife is a third vegetation to two thirds open water!

If the space you live in is especially wet, you might consider having your pond liner extend beyond the pond, creating an overspill area for times of high rainfall. These can be ‘wet meadows’ or ‘bog gardens’, which provide a space for plants that love soggy soil, including Soft Rush, Ragged Robin or Water Forget-me-not. Acid soil is ideal for Sphagnum Moss – a hero bog species if ever there was one.

Be sure to include adjacent dense vegetation or refugia (old bricks, rotten logs) so amphibians can safely reach your pond without fear of exposure to predators.

Raised ponds are increasingly popular, usually because they are harder for small children to access. However, these present a challenge to frogs, toads and other terrestrial wildlife, which means you’ll only get insects, no tadpoles (which as any child will tell you, are usually the highlight of a pond!).

Simple adaptations might include a wire mesh frame, pinned with heavy stones/lockable hinge in a school setting (with gaps large enough for wildlife to move through safely) or fencing off a small area for your pond.

Then it’s time to fill it! Rainwater is your best bet, due to its low nutrient content compared to tap water, which can lead to algal blooms. Tap water also contains chemicals which can be harmful to wildlife, such as chlorine, so it’s best to let the sky fill it up if you can.

However you do it, creating a pond is one of the greatest ways to add value in your garden for wildlife. Ponds across the UK have declined rapidly in the last few years, and any watery habitat will be much appreciated by wild creatures, from garden birds to toads, those you already have to the new species you’ll soon attract.

For more tips on pond creation, visit: www.montwt.co.uk/actions/how-build-pond

PICTURES:

Garden Pond: Shallow areas, with rocks, enable insects, mammals and amphibians to get in and out of your pond without getting trapped. Photo: © Tom Marshall

Common Frog: Garden ponds provide ideal, and increasingly vital, breeding grounds for frogs, and children will be delighted to watch frogspawn turn into hopping, croaking wonders. Photo: Mark Hamblin/2020VISION